Simi, a professor of criminology at the University of Nebraska, Omaha, and co-author of American Swastika, realized that he had talked to Page at length during his research on the white power movement in the United States.

Simi spoke to All Things Considered's Melissa Block this afternoon and told her that he has been thinking about whether he missed any red flags, anything that could have foretold a mass shooting.

Page, said Simi, certainly had a drinking problem and he also had a problem holding a job. He had tattoos and he saw a couple of rifles and was steeped in the music scene that drives the neo-Nazi skinhead groups.

Still, he said, "there wasn't anything that stood out, that really made me think that he was more of a threat than other people who hold these beliefs."

In other words, within the world of white power, where the rhetoric is often violent, Page was normal.

"This makes trying to determine who is more likely to be a threat extremely complicated and very difficult to do," he said.

Simi also said that he spoke to Page at length about his time in the military. Page told him that before he went into the military he had heard about the white power philosophy but the "military to him was an important experience in shaping how he saw the world."

"He told me specifically that if you don't go into the military a racist, you are certain to leave as one," Simi said. "He suggested that in the military the deck was completely stacked against white people, that African American personnel in the military were routinely promoted over whites when they didn't deserve it, that they weren't disciplined for misconduct, that they were coddled, that they were treated very preferentially as compared to whites."

When he left the military, Simi said, he came to believe that "the whole system was set up against whites."

Listen for Melissa's full interview with Simi on tonight's All Things Considered. We'll post audio of the as-aired interview later on tonight.

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MELISSA BLOCK, HOST:

We're joined now a researcher who studies the white supremacy movement and who met and interviewed the Wisconsin shooter, Wade Page, over the course of several years, starting in 2001. Pete Simi is co-author of "American Swastika." He teaches criminology at the University of Nebraska, Omaha. Pete Simi, welcome to the program.

PETE SIMI: Thanks for having me.

BLOCK: You met Wade Page when he was living in Southern California. He was living with another white supremacist that you were following. What did he tell you about how he became part of this hate movement, the white power movement?

SIMI: The way Page explained it to me was that he had been aware of racist skinheads and other white supremacists during late adolescence. He was involved in a punk music scene and had some, you know, minor contacts with some of those folks, but didn't necessarily, you know, identify with them or define himself in such a way. But that it was during his time in the military that he really began to see himself and define himself within these neo-Nazi terms, white supremacists.

And at that point in time, during his military years, he actually met some individuals who were also in the military that were already involved.

BLOCK: Wade Page was stationed at Fort Bragg back in the 1990s at a time when a number of white supremacist groups were found to be very entrenched there on base. And, in fact, there were two neo-Nazi soldiers who were convicted of killing a black couple nearby in the '90s. What did he say about the overall culture of white supremacists in the military, in particular at Fort Bragg at that time?

SIMI: You know, he said it was around. The way he explained it to me was that the military for him was really an important experience in shaping how he saw the world. He told me that, specifically, that if you don't go into the military a racist, you're certain to leave as one.

BLOCK: Did he explain what he meant by that?

SIMI: Yes, he did. He suggested that the military was - the deck was completely stacked against white people. That African-American personnel in the military were routinely promoted over whites when they didn't deserve it, that they weren't disciplined for misconduct, that they were coddled, as compared to whites. And he came to feel that, you know, basically the military organization, the system, was completely set up against whites.

BLOCK: I want to talk to you about another aspect of Wade Page's background and that's the role of hate music. He was very involved in a number of white power bands, hate-core bands. Here's a bit of a song called "Self Destruct" from one of his bands known as End Apathy.

(SOUNDBITE OF "SELF DESTRUCT")

BLOCK: So we're hearing him in that song saying self-destruct, self-destruct, self-destruct. There would be a lot of hate-core lyrics, though, that would be far more violent and explicit than that, right?

SIMI: Oh, absolutely. Some of the lyrics are very, very explicit, you know, advocating, you know, lynchings and beatings and other, you know, violent acts. But then, you know, it is important to point out that that's not all of the lyrics, that there is a pretty wide kind of cross section within this genre of, you know, white power and neo-Nazi music.

And some of the lyrics are much more subtle, innocuous and, you know, much more kind of coded.

BLOCK: And I've seen lists of hundreds of these bands with names like Ethnic Cleansing, Angry Aryans, Kill Or Be Killed. What's the role that this hate music movement plays within the supremacist movement itself?

SIMI: Well, the music is central to the movement in a lot of ways. It played a vital role in terms of offering opportunities for potential recruitment, offering opportunities for the generation of revenue and then probably most importantly, you know, music pulls people together. It gives them opportunities to get together for music shows, music festivals; small shows, large ones, coming together on the Internet and talking about music shows.

All of these are opportunities for them to share in these kinds of occasions where they're talking, you know, spending time with, communicating with like-minded others who share the same view of the world as they do and talking about, you know, the future and what needs to be done.

BLOCK: Pete Simi, when you first realized that the killer in Wisconsin was, in fact, Wade Page, this man whom you'd spent time with, interviewed over a number of years, what did you think? Did you think back to anything that he had told you that said, yeah, he has actually put his supremacist beliefs into action and I could see this would happen?

SIMI: Well, when I initially found out that it was Page, you know, I felt disgusted. I felt sickened, it was very surreal. But certainly, you know, I began to try and process and think about the time I spent with him, think about the experiences. And, you know, yeah, there's a few things that stand out in retrospect. He had, you know, definitely had a drinking problem. But again, that's not all that uncommon in this world.

Drinking is pretty central, especially to the white power, neo-Nazi, skinhead culture. You know, he had an unstable work record, but again, there are certainly other individuals that are part of this world who also have problems keeping a job, you know, holding a job down. You know, yeah, he had a lot of tattoos, you know. He was starting to tattoo his body, you know, with symbols associated with neo-Nazism.

You know, in retrospect, you know, there certainly are some things that may be important in terms of trying to understand what led him to what he ultimately did. But if you have red flags that are pretty common, then they don't - they're not all that helpful in terms of trying to assess potential threat.

BLOCK: Pete Simi, thanks for talking with us today.

SIMI: Thanks for having me.

BLOCK: That's Pete Simi of the University of Nebraska, Omaha. His book is "American Swastika: Inside the White Power Movement's Hidden Spaces of Hate." Transcript provided by NPR, Copyright NPR.